1. Field of the Invention
This invention relates to improvements in an electronic level and specifically to improvements in the visual display, providing an audible tone indication of level, and providing sensing in all inclination positions of the level.
2. Description of the Prior Art
Electronic levels known in the art include that sold by Wedge Innovations Inc. and what is disclosed in U.S. Pat. No. 4,912,662 issued Mar. 27, 1990 to Butler et al. (assigned to Wedge Innovations Inc.). The displays of these levels tend to be relatively difficult to read in terms of the amount of inclination from the desired null position (typically level or plumb). Furthermore, prior art electronic level displays such as that disclosed by Butler et al. show the inclination in degrees or percent slope, which are typically not the inclination measurements used by tradesmen (carpenters, masons etc.). Prior art devices often do not provide a satisfactory indication of how far from level or plumb one is, and are not very useful for indicating inclinations other than level or plumb, such as some arbitrary angle, unless one is able to read the display.
Furthermore, typical prior art levels do not indicate audibly to what extent one is off level or off plumb. Additionally, the prior art devices are relatively slow to respond.